Tag Archives: reservoir
At present time the interest to the quantitative interpretation of temperature surveys is growing. Individual flow rate and reservoir pressure of each layer, behind-casing flow rate, hydrodynamic layer parameters, characterization of permeability changing at near-wellbore zone become the purposes of quantitative interpretation. Non-stationary temperature and pressure in the well are used as input data for transient processes analysis, and temperature logs are used for quasi-stationary analysis. Particular interest is in determination of the individual layer flow rates and near-wellbore zone parameters.
The paper studies the problem of unsteady temperature field in heterogeneous reservoir during fluid filtration. The aim of this work was to develop and provide rationale for simplified analytical model of non-isothermal single-phase fluid filtration in heterogeneous reservoir. Analytical solution for the temperature field in the formation after flow rate changeis obtained by the method of characteristics. Two assumptions were made in solving the problem: radial thermal conduction and compressibility of saturated porous medium are ignored. Analytical models are compared with the numerical solution of the problem. Radial heat conduction and compressibility of oil- or water-saturated reservoirs influence insignificantly on the unsteady temperature field after the flow rate changes.
It is possible to solve the inverse problem on the evaluation of the damage zone radius of the permeability in the reservoir basing on the model curves of the temperature change after flow rate change. The possibility of that method realization is demonstrated on model curves of the temperature change.
GEOLOGICAL-TECHNICAL MEASURES FOR CONTROL AND REGULATION OF DEVELOPMENT OF DEPOSITS OF KOGALYM GROUP IN CONCLUDING STAGE
The article discusses the most effective interventions stimulation in a wedge-like structure of deposits for large deposit Kogalym group.
Showing: realization of the cards remaining recoverable oil reserves with the help of three-dimensional geological and hydrodynamic modeling; selection of promising areas with the highest concentration of the density of residual stocks and taking into account the peculiarities of sedimentation.
Based on statistical modeling of the effectiveness of a number of completed projects of hydraulic fracturing (frac), highlighted the most influential factors and favorable zones identified the success of the recommended measures. Selection of sites was performed by grouping wells using a fracturing and the degree of efficiency. The dependences obtained are consistent with the characteristics of sedimentation and ranking analyzed geological and reservoir on the fishing grounds. The criteria applying hydraulic fracturing with our additions.
The effective application of hydrodynamic EOR methods implemented a complex interaction of injection wells to production, is based on obtaining maps line filtering and Spearman rank coefficient. As a result of these implementations, and selected portions of the well-candidates for new types of hydrodynamic EOR.
On the basis of the establishment of the correlation relationship between the production and injection wells were selected group of wells to be able to use technologies of non-stationary flooding and changing the direction of filtration flows. Selection of the duration of the cycles carried out by the formula VI Shchelkachev based on the calculation piezoconductivity formation. For wells with a cycle of more than 80 days is considered an option activities change direction of filtration flows. For all variants forecast oil production is estimated by calculating the hydrodynamic simulation.
Studies conducted in the framework of the State Scientific and Technical Program «Bashkortostan 2020 – The rational use of natural resources and the modernization of oil and gas technologies» and with the support of the CCI «Kogalymneftegas».
OIL AND GAS FIELDS IN ZHUNGEER BASIN AND THE PROBLEMS OF THEIR EXPLORATION IN THE NORTHWEST OF CHINA
Zhungeer Basin is located in the province of Xinjiang in northwest China. It has an area of 130 km2. In tectonic terms, this trap is immersed in south-eastern direction. Zhungeer Basin is made by continental deposits from the Permian to Miocene age with a total capacity of 14 thousand meters Permian source rocks, represented by high carbon clay deposits, developed in the southern part of the basin. Oil has migrated over the surfaces of disagreements and accumulated in the lenses of sandstones and conglomerates in the sediments of the Carboniferous, Upper Permian, Middle and Upper Triassic, Upper Jurassic and Miocene (C, P2, T2-3, J3, N1).
Within the Zhungeer Basin yet are identified 5 oil-bearing formations, which are dispersed in the Carboniferous and Permian sediments. Most common oil-bearing interval reaches 800-900 m. In 2008 was completed a drilling with a depth of 2010 m. When testing two-meter reservoir sandstones of Carboniferous age in the range of 605-698 m, we obtained 527 tons of oil and 1,200 m3 of gas on the nozzle 5 mm. In addition, high viscous oil also was discovered.
This paper discusses the geological and production characteristics of the main oil and gas fields of the Zhungeer basin. It was Investigated in detail the structural features, the history of the discovery and formation of hydrocarbons, dissemination and preservation of oil and gas deposits. To establish geological structures and Mesozoic thickness, which is possibly promising for oil and gas, research of the university within the state scientific and technical program “Sustainable development of natural resources and modernization of oil and gas technologies” (from 2012) and program of the China University of Petroleum “Energy program and the development of China” (from 2010) is in process.
THE SELECTION OF COMPLEX RESERVOIRS OF HYDROCARBONS OPENED ON SALINE FLUSH DRILLING FLUIDS IN DEEP EXPLORATORY WELLS
We have investigated the usefulness of GIS methods (geophysical investigations in boreholes) and GTI (mud logging) in distinguishing low-power numerous collectors HC (hydrocarbons) in deep exploratory wells, complicated by the high caverns and drilled for saline drilling fluid. Limitations of techniques emisions and determine their characteristics leads to skipping of productive intervals and their erroneous selection. Data electrical methods (BKZ (lateral sounding), MKZ (microcerotermes sensing), IR (induction logging), PS (logging potentials spontaneous polarization)) in terms of the mineralized mud and cavernous wellbore distorted, poorly reflect the incision and therefore uninformative. There are no direct characteristics collector – positive increment on the microprobes (MHS (micro-gradient probe), MPZ (micro-potential probe) and clay crust against the collector by DS (inspection), at the substation are not marked minimum values of the net (Neglinnaya) terrigenous formations. Saturated and reservoirs on IR also not differentiated. Readings radioactive methods (COG (neutron gamma logging) and GGC-p (gamma-gamma density logs)) are distorted by the presence of large cavities in the wellbore. For successful execution of exploration drilling designed research methodology perspective on HC intervals. The method is based on an integrated use of all possible methods of GIS, the GTI and direct methods for the steady reservoir and determine their characteristics. Proposed rational complex GIS detailed geophysical studies in Sandstone reservoirs, exploration and appraisal wells drilled in saline solutions.
ABOUT THE INFLUENCE OF GEOLOGICAL HETEROGENEITY OF MOUTH BAR ON THE HYDRODYNAMICS OF THE RESERVOIR ROCK OF RED FOREST FIELD (CHINA)
The article considers the geological structure of C6 productive bed of Red forest oilfield (China). It is determined that reservoir rock belongs to mouth bar of delta front. The survey shows the laminated structure of the reservoir, consisting of several regressive sedimentation cyclical beds separated by impermeable clay layers. In the structure of the regression mouth bar are dedicated two subfacies: crest and slope. It is established that crest subfacie is characterized by high grain maturity and made more powerful and homogeneous sandy sediments with high permeability properties. Slope subfacie of mouth bar has a high stratification with frequent interlayering of discontinuous thin sand bodies composed of immature sediments with the deterioration of reservoir properties.
The presence of macroheterogeneity in bar sediments determines the filtration reservoir structure and its dynamics that must be considered when selecting the system of the injection wells location, the design of horizontal wells and design of hydraulic fracturing. It is shown that the most significant effect on the fluid dynamics of the reservoir have a layered structure of the reservoir, the location of injection and production wells in relation to the bar body and, especially, differences in the azimuthal direction of seepage flow and the strike of mouth bar sand bodies. The simulation results showed that the reservoir with a large number of layers is watered with more effectively, and the amount of remaining oil in it more than in the reservoir with a small number of layers; quick the water-cut and the decline in oil production are established in models where the sand body strike coincides with the direction of fluid flow. Recommendations on the organization of the flooding system for optimal oil extraction of laminated heterogeneous bar reservoir.